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  1. if ~defined newprocess_inc
  2. newprocess_inc_fix:
  3. newprocess_inc fix newprocess_inc_fix
  4. include "mem.inc"
  5. include "memmanag.inc"
  6. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  7. ;;Working with new types of processes.
  8. ;;Author: Khalyavin Andrey halyavin@land.ru
  9. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  10. iglobal
  11.     new_process_loading db 'K : New Process - loading',13,10,0
  12.     new_process_running db 'K : New Process - done',13,10,0
  13.     start_not_enough_memory db 'K : New Process - not enough memory',13,10,0
  14. endg
  15. ;-----------------------------------------------------------------------------
  16.  
  17. find_new_process_place:
  18. ;input:
  19. ;  none
  20. ;result:
  21. ;  eax=[new_process_place]<>0 - ok
  22. ;      0 - failed.
  23. ;This function find least empty slot.
  24. ;It doesn't increase [0x3004]!
  25.     mov    eax,0x3000+second_base_address
  26.     push   ebx
  27.     mov    ebx,[0x3004]
  28.     inc    ebx
  29.     shl    ebx,5
  30.     add    ebx,eax               ;ebx - address of process information for (last+1) slot
  31. .newprocessplace:
  32. ;eax = address of process information for current slot
  33.     cmp    eax,ebx
  34.     jz     .endnewprocessplace   ;empty slot after high boundary
  35.     add    eax,0x20
  36.     cmp    word [eax+0xa],9      ;check process state, 9 means that process slot is empty
  37.     jnz    .newprocessplace
  38. .endnewprocessplace:
  39.     mov    ebx,eax
  40.     sub    eax,0x3000+second_base_address
  41.     shr    eax,5                 ;calculate slot index
  42.     cmp    eax,256
  43.     jge    .failed               ;it should be <256
  44.     mov    word [ebx+0xa],9      ;set process state to 9 (for slot after hight boundary)
  45.     mov    [new_process_place],eax ;save process slot
  46.     pop    ebx
  47.     ret    
  48. .failed:
  49.     xor    eax,eax
  50.     pop    ebx
  51.     ret
  52. ;-----------------------------------------------------------------------------
  53.  
  54. new_start_application_floppy:
  55. ;input:
  56. ;  eax - pointer to filename
  57. ;  ebx - parameters to pass
  58. ;result:
  59. ;  eax - pid of new process
  60. ;        or 0 if call fails.
  61.     pushad
  62.     mov    esi,new_process_loading
  63.     call   sys_msg_board_str     ;write to debug board
  64.    
  65. ;wait application_table_status mutex
  66. .table_status:    
  67.     cli
  68.     cmp    [application_table_status],0
  69.     jz     .stf
  70.     sti
  71.     call   change_task
  72.     jmp    .table_status
  73. .stf:
  74.     call   set_application_table_status
  75. ;we can change system tables now
  76.     push   edi
  77.     push   ebx
  78.     push   eax
  79.     call   find_new_process_place ;find empty process slot
  80.     sti
  81.     test   eax,eax
  82.     jz     .failed
  83.  
  84.     mov    edi,eax
  85.     shl    edi,8
  86.     add    edi,0x80000
  87.     mov    ecx,256/4
  88.     xor    eax,eax
  89.     cld
  90.     rep    stosd                 ;clean extended information about process
  91.    
  92. ;set new process name
  93.     mov    eax,[esp+8]
  94. .find_last_byte:
  95.     cmp    byte [eax],0    
  96.     jz     .find_last_byte_end
  97.     inc    eax
  98.     jmp    .find_last_byte
  99. .find_last_byte_end:    
  100.     sub    eax,11                ;last 11 bytes = application name
  101. ;    mov    eax,[esp]             ;eax - pointer to file name
  102.     mov    ebx,[new_process_place]
  103.     shl    ebx,8
  104.     add    ebx,0x80000
  105.     mov    ecx,11
  106.     call   memmove
  107.      
  108. ;read header of file
  109.     mov    eax,[esp]
  110.     mov    ebx,1                 ;index of first block
  111.     mov    ecx,2                 ;number of blocks
  112.     mov    edx,0x90000           ;temp area
  113.     mov    esi,12                ;file name length
  114.     mov    edi,[esp+8]
  115. ;    cli
  116.     call   floppy_fileread       ;read file from FD
  117. ;    sti
  118.     cmp    eax,0
  119.     jne    .cleanfailed
  120. ;check MENUET signature    
  121.     cmp    [0x90000],dword 'MENU'
  122.     jnz    .cleanfailed
  123.     cmp    [0x90004],word 'ET'
  124.     jnz    .cleanfailed
  125.    
  126.     call   get_app_params        ;parse header fields
  127.     cmp    esi,0
  128.     jz     .cleanfailed
  129.    
  130.     mov    eax,[new_process_place]
  131.     call   create_app_cr3_table   ;create page directory for new process
  132.     test   eax,eax
  133.     jz     .cleanfailed_mem
  134.    
  135.     call   MEM_Get_Linear_Address ;calculate linear address of it
  136.    
  137.     mov    ebx,std_application_base_address
  138.     mov    ecx,[app_mem]
  139.     add    ecx,4095
  140.     shr    ecx,12
  141.     mov    edx,eax
  142.     call   mem_alloc_specified_region ;allocate memory for application
  143.     test   eax,eax
  144.     jz     .cleanfailed_mem
  145.    
  146.     mov    eax,[edx+(std_application_base_address shr 20)]
  147.     and    eax,not (4096-1)      ;eax - physical address of first (for application memory) page table
  148.     call   MEM_Get_Linear_Address
  149.     mov    edx,eax
  150.  
  151. ;read file
  152.     mov    ebx,1
  153.     mov    esi,12                ;length of file name
  154. .loop1:
  155. ;edx = linear address of current page table entry
  156. ;ebx = index of current block in file
  157.     push   edx
  158.     mov    eax,[edx]
  159.     and    eax,not (4096-1)
  160.     call   MEM_Get_Linear_Address
  161.     mov    edx,eax               ;read file block to current page
  162.     mov    eax,[esp+4]           ;restore pointer to file name
  163.     mov    ecx,8                 ;number of blocks read
  164.     push   ebx
  165.     mov    edi,[esp+16]    
  166. ;    cli
  167.     call   floppy_fileread
  168. ;ebx=file size    
  169. ;    sti
  170.     pop    ecx
  171.     shr    ebx,9
  172.     cmp    ecx,ebx
  173.     jg     .endloop1             ;if end of file?
  174.     mov    ebx,ecx
  175.     test   eax,eax              
  176.     jnz    .endloop1             ;check io errors
  177.     pop    edx
  178.     add    ebx,8                 ;go to next page
  179.     add    edx,4
  180.     jmp    .loop1
  181.    
  182. .endloop1:
  183.     add    esp,8+4                 ;pop linear address of page table entry and pointer to file name
  184.     call   new_start_application_fl.add_app_parameters
  185.     mov    [esp+28],eax
  186.     popad
  187.     ret
  188. .cleanfailed_mem:
  189.     mov    esi,start_not_enough_memory
  190.     call   sys_msg_board_str
  191. .cleanfailed:                    ;clean process name
  192.     mov    edi,[new_process_place]
  193.     shl    edi,8
  194.     add    edi,0x80000
  195.     mov    ecx,11
  196.     mov    eax,' '
  197.     cld
  198.     rep    stosb
  199. .failed:
  200.     add    esp,8+4
  201.     mov    [application_table_status],0
  202.     popad
  203.     sti
  204.     mov    eax,-1
  205.     ret  
  206.  
  207. ;-----------------------------------------------------------------------------    
  208. new_start_application_fl:
  209. ;input:
  210. ;  eax - pointer to filename
  211. ;  ebx - parameters to pass
  212. ;result:
  213. ;  eax - pid of new process
  214. ;        or 0 if call fails.
  215.     pushad
  216.     mov    esi,new_process_loading
  217.     call   sys_msg_board_str     ;write to debug board
  218.    
  219. ;wait application_table_status mutex
  220. .table_status:    
  221.     cli
  222.     cmp    [application_table_status],0
  223.     jz     .stf
  224.     sti
  225.     call   change_task
  226.     jmp    .table_status
  227. .stf:
  228.     call   set_application_table_status
  229. ;we can change system tables now    
  230.     push   ebx
  231.     push   eax
  232.     call   find_new_process_place ;find empty process slot
  233.     sti
  234.     test   eax,eax
  235.     jz     .failed
  236.  
  237.     mov    edi,eax
  238.     shl    edi,8
  239.     add    edi,0x80000
  240.     mov    ecx,256/4
  241.     xor    eax,eax
  242.     cld
  243.     rep    stosd                 ;clean extended information about process
  244.    
  245. ;set new process name
  246.     mov    eax,[esp]             ;eax - pointer to file name
  247.     mov    ebx,[new_process_place]
  248.     shl    ebx,8
  249.     add    ebx,0x80000
  250.     mov    ecx,11
  251.     call   memmove
  252.      
  253. ;read header of file
  254.     mov    ebx,1                 ;index of first block
  255.     mov    ecx,2                 ;number of blocks
  256.     mov    edx,0x90000           ;temp area
  257.     mov    esi,12                ;file name length
  258.     cli
  259.     call   fileread              ;read file from RD
  260.     sti
  261.     cmp    eax,0
  262.     jne    .cleanfailed
  263. ;check MENUET signature    
  264.     cmp    [0x90000],dword 'MENU'
  265.     jnz    .cleanfailed
  266.     cmp    [0x90004],word 'ET'
  267.     jnz    .cleanfailed
  268.    
  269.     call   get_app_params        ;parse header fields
  270.     cmp    esi,0
  271.     jz     .failed
  272.    
  273.     mov    eax,[new_process_place]
  274.     call   create_app_cr3_table   ;create page directory for new process
  275.     test   eax,eax
  276.     jz     .cleanfailed_mem
  277.    
  278.     call   MEM_Get_Linear_Address ;calculate linear address of it
  279.    
  280.     mov    ebx,std_application_base_address
  281.     mov    ecx,[app_mem]
  282.     add    ecx,4095
  283.     shr    ecx,12
  284.     mov    edx,eax
  285.     call   mem_alloc_specified_region ;allocate memory for application
  286.     test   eax,eax
  287.     jz     .cleanfailed_mem
  288.    
  289.     mov    eax,[edx+(std_application_base_address shr 20)]
  290.     and    eax,not (4096-1)      ;eax - physical address of first (for application memory) page table
  291.     call   MEM_Get_Linear_Address
  292.     mov    edx,eax
  293.  
  294. ;read file
  295.     mov    ebx,1
  296.     mov    esi,12                ;length of file name
  297. .loop1:
  298. ;edx = linear address of current page table entry
  299. ;ebx = index of current block in file
  300.     push   edx
  301.     mov    eax,[edx]
  302.     and    eax,not (4096-1)
  303.     call   MEM_Get_Linear_Address
  304.     mov    edx,eax               ;read file block to current page
  305.     mov    eax,[esp+4]           ;restore pointer to file name
  306.     mov    ecx,8                 ;number of blocks read
  307.     push   ebx
  308.     cli
  309.     call   fileread
  310. ;ebx=file size    
  311.     sti
  312.     pop    ecx
  313.     shr    ebx,9
  314.     cmp    ecx,ebx
  315.     jg     .endloop1             ;if end of file?
  316.     mov    ebx,ecx
  317.     test   eax,eax              
  318.     jnz    .endloop1             ;check io errors
  319.     pop    edx
  320.     add    ebx,8                 ;go to next page
  321.     add    edx,4
  322.     jmp    .loop1
  323.    
  324. .endloop1:
  325.     add    esp,8                 ;pop linear address of page table entry and pointer to file name
  326.     call   .add_app_parameters
  327.     mov    [esp+28],eax
  328.     popad
  329.     ret
  330.    
  331. .cleanfailed_mem:
  332.     mov    esi,start_not_enough_memory
  333.     call   sys_msg_board_str
  334. .cleanfailed:                    ;clean process name
  335.     mov    edi,[new_process_place]
  336.     shl    edi,8
  337.     add    edi,0x80000
  338.     mov    ecx,11
  339.     mov    eax,' '
  340.     cld
  341.     rep    stosb
  342. .failed:
  343.     add    esp,8
  344.     mov    [application_table_status],0
  345.     popad
  346.     sti
  347.     mov    eax,-1
  348.     ret
  349.        
  350. .add_app_parameters:
  351. ;input:
  352. ;  [esp] - pointer to parameters
  353. ;  [esp+4]-[esp+36] pushad registers.
  354. ;result
  355. ;  eax - pid of new process
  356. ;        or zero if failed
  357.     cli
  358.     mov    ebx,[new_process_place]
  359.     cmp    ebx,[0x3004]
  360.     jle    .noinc
  361.     inc    dword [0x3004]        ;update number of processes
  362. .noinc:
  363.  
  364. ;   mov    ebx,[new_process_place]
  365. ;set 0x8c field of extended information about process
  366. ;(size of application memory)
  367.     shl    ebx,8
  368.     mov    eax,[app_mem]
  369.     mov    [second_base_address+0x80000+0x8c+ebx],eax            
  370. ;set 0x10 field of information about process
  371. ;(application base address)    
  372. ;    mov    ebx,[new_process_place]
  373. ;    shl    ebx,5
  374.     shr    ebx,3
  375.     mov    dword [second_base_address+0x3000+ebx+0x10],std_application_base_address
  376.  
  377. ;add command line parameters
  378. .add_command_line:
  379.     mov    edx,[app_i_param]
  380.     test   edx,edx
  381.     jz     .no_command_line      ;application don't need parameters
  382.     mov    eax,[esp+4]
  383.     test   eax,eax
  384.     jz     .no_command_line      ;no parameters specified
  385. ;calculate parameter length    
  386.     mov    esi,eax
  387.     xor    ecx,ecx
  388. .command_line_len:
  389.     cmp    byte [esi],0
  390.     jz     .command_line_len_end
  391.     inc    esi
  392.     inc    ecx
  393.     cmp    ecx,256
  394.     jl     .command_line_len
  395.    
  396. .command_line_len_end:
  397. ;ecx - parameter length
  398. ;edx - address of parameters in new process address space
  399.     mov    ebx,eax               ;ebx - address of parameters in our address space
  400.     mov    eax,[new_process_place]
  401.     call   write_process_memory  ;copy parameters to new process address space
  402.    
  403. .no_command_line:
  404.     mov    ebx,[new_process_place]
  405.     mov    eax,ebx
  406.     shl    ebx,5
  407.     add    ebx,0x3000            ;ebx - pointer to information about process
  408.     mov    [ebx+0xe],al          ;set window number on screen = process slot
  409.    
  410.     mov    [ebx],dword 1+2+4     ;set default event flags (see 40 function)
  411.    
  412.     inc    dword [process_number]
  413.     mov    eax,[process_number]
  414.     mov    [ebx+4],eax           ;set PID
  415.    
  416.     mov    ecx,ebx
  417.     add    ecx,draw_data-0x3000  ;ecx - pointer to draw data
  418. ;set draw data to full screen    
  419.     mov    [ecx+0],dword 0      
  420.     mov    [ecx+4],dword 0
  421.     mov    eax,[0xfe00]
  422.     mov    [ecx+8],eax
  423.     mov    eax,[0xfe04]
  424.     mov    [ecx+12],eax
  425. ;set cr3 register in TSS of application    
  426.     mov    ecx,[new_process_place]    
  427.     shl    ecx,8
  428.     mov    eax,[0x800B8+ecx]
  429.     add    eax,8+16              ;add flags
  430.     mov    [l.cr3],eax
  431. ;write cr3 in TSS of System Call Handler    
  432.     mov    ecx,[new_process_place]
  433.     shl    ecx,7
  434.     mov    [0x298000+ecx+l.cr3-tss_sceleton],eax   ;write directy to TSS
  435.    
  436.     mov    eax,[app_start]
  437.     mov    [l.eip],eax           ;set eip in TSS
  438.     mov    eax,[app_esp]
  439.     mov    [l.esp],eax           ;set stack in TSS
  440.    
  441. ;gdt
  442.     mov    ebx,[new_process_place]
  443.     shl    ebx,3
  444.     mov    ax,app_code           ;ax - selector of code segment
  445.     add    ax,bx
  446.     mov    [l.cs],ax
  447.     mov    ax,app_data
  448.     add    ax,bx                 ;ax - selector of data segment
  449.     mov    [l.ss],ax
  450.     mov    [l.ds],ax
  451.     mov    [l.es],ax
  452.     mov    [l.fs],ax
  453.     mov    ax,graph_data         ;ax - selector of graphic segment
  454.     mov    [l.gs],ax
  455.     mov    [l.io],word 128
  456.     mov    [l.eflags],dword 0x11202
  457.     mov    [l.ss0],os_data
  458.     mov    [l.esp0],0x55000
  459. ;    mov    [l.esp1],0x56000
  460. ;    mov    [l.esp2],0x57000
  461.  
  462. ;copy tss to it place
  463.     mov    eax,tss_sceleton
  464.     mov    ebx,[new_process_place]
  465.     imul   ebx,tss_step
  466.     add    ebx,tss_data          ;ebx - address of application TSS
  467.     mov    ecx,120              
  468.     call   memmove
  469.    
  470. ;Add IO access table - bit array of permitted ports
  471.     or     eax,-1
  472.     mov    edi,[new_process_place]
  473.     imul   edi,tss_step
  474.     add    edi,tss_data+128
  475.     mov    ecx,2048
  476.     cld
  477.     rep    stosd                 ;full access to 2048*8=16384 ports
  478.    
  479.     mov    ecx,ebx               ;ecx - address of application TSS
  480.     mov    edi,[new_process_place]
  481.     shl    edi,3
  482. ;set TSS descriptor
  483.     mov    [edi+gdts+tss0+0],word tss_step ;limit (size)
  484.     mov    [edi+gdts+tss0+2],cx  ;part of offset
  485.     mov    eax,ecx
  486.     shr    eax,16
  487.     mov    [edi+gdts+tss0+4],al  ;part of offset
  488.     mov    [edi+gdts+tss0+7],ah  ;part of offset
  489.     mov    [edi+gdts+tss0+5],word 01010000b*256+11101001b ;system flags
  490.    
  491. ;set code and data segments
  492.     mov    eax,[new_process_place]
  493.     shl    eax,3
  494. ;set base address of code segment
  495.     mov    word [eax+gdts+app_code-3+2],0
  496.     mov    byte [eax+gdts+app_code-3+4],0
  497.     mov    byte [eax+gdts+app_code-3+7],std_application_base_address shr 24
  498. ;set limit of code segment
  499. ;    mov    ebx,[app_mem]
  500. ;    add    ebx,4095
  501. ;    shr    ebx,12
  502.     mov    ebx,(0x80000000-std_application_base_address) shr 12
  503.     mov    [eax+gdts+app_code-3+0],bx
  504.     mov    [eax+gdts+app_code-3+5],word 11010000b*256+11111010b+256*((0x80000000-std_application_base_address) shr 28)
  505. ;set base address of data segment
  506.     mov    word [eax+gdts+app_data-3+2],0
  507.     mov    byte [eax+gdts+app_data-3+4],0
  508.     mov    byte [eax+gdts+app_data-3+7],std_application_base_address shr 24
  509. ;set limit of data segment
  510.     mov    [eax+gdts+app_data-3+0],bx
  511.     mov    [eax+gdts+app_data-3+5],word 11010000b*256+11110010b+256*((0x80000000-std_application_base_address) shr 28)
  512.      
  513.  
  514. ;flush keyboard and buttons queue
  515.     mov    [0xf400],byte 0
  516.     mov    [0xf500],byte 0
  517.  
  518.     mov    edi,[new_process_place]
  519.     shl    edi,5
  520.     add    edi,window_data
  521.     mov    ebx,[new_process_place]
  522.     movzx  esi,word [0xC000+ebx*2]
  523.     lea    esi,[0xC400+esi*2]
  524.     call   windowactivate        ;gui initialization
  525.  
  526.     mov    ebx,[new_process_place]
  527.     shl    ebx,5
  528.     mov    [0x3000+ebx+0xa],byte 0 ;set process state - running
  529.    
  530.     mov    esi,new_process_running
  531.     call   sys_msg_board_str     ;output information about succefull startup
  532.    
  533. ;    add    esp,4                 ;pop pointer to parameters
  534. ;    popad
  535.     mov    eax,[process_number]  ;set result
  536.     mov    [application_table_status],0 ;unlock application_table_status mutex
  537.     sti
  538.     ret    4
  539. ;-----------------------------------------------------------------------------    
  540. new_sys_threads:
  541. ;eax=1 - create thread
  542. ;   ebx=thread start
  543. ;   ecx=thread stack value
  544. ;result:
  545. ;   eax=pid
  546.     pushad
  547.    
  548.     cmp    eax,1
  549.     jnz    .ret                  ;other subfunctions
  550.     mov    esi,new_process_loading
  551.     call   sys_msg_board_str
  552. ;lock application_table_status mutex
  553. .table_status:    
  554.     cli
  555.     cmp    [application_table_status],0
  556.     je     .stf
  557.     sti
  558.     call   change_task
  559.     jmp    .table_status
  560. .stf:
  561.     call   set_application_table_status
  562. ;find free process slot
  563.  
  564.     call   find_new_process_place
  565.     test   eax,eax
  566.     jz     .failed
  567.    
  568. ;set parameters for thread
  569.     xor    eax,eax
  570.     mov    [app_i_param],eax
  571.     mov    [app_i_icon],eax
  572.     mov    [app_start],ebx
  573.     mov    [app_esp],ecx
  574.  
  575.     mov    esi,[0x3000]
  576.     shl    esi,8
  577.     add    esi,0x80000
  578.     mov    ebx,esi               ;ebx=esi - pointer to extended information about current thread
  579.    
  580.     mov    edi,[new_process_place]
  581.     shl    edi,8
  582.     add    edi,0x80000
  583.     mov    edx,edi               ;edx=edi - pointer to extended infomation about new thread
  584.     mov    ecx,256/4
  585.     rep    stosd                 ;clean extended information about new thread
  586.     mov    edi,edx
  587.     mov    ecx,11
  588.     rep    movsb                 ;copy process name
  589.     mov    eax,[ebx+0x8c]
  590.     mov    [app_mem],eax         ;set memory size
  591.     mov    eax,[ebx+0xb8]
  592.     mov    [edx+0xb8],eax        ;copy page directory
  593. ;    mov    eax,[new_process_place]
  594. ;    mov    ebx,[0x3000]
  595. ;    call   addreference_app_cr3_table
  596.  
  597.     push   0                     ;no parameters
  598.     call    new_start_application_fl.add_app_parameters ;start thread
  599.     mov    [esp+28],eax
  600.     popad
  601.     ret
  602.    
  603. .failed:
  604.     sti
  605.     popad
  606.     mov    eax,-1
  607.     ret    
  608. .ret:
  609.     popad
  610.     ret
  611. ;-----------------------------------------------------------------------------    
  612. new_mem_resize:
  613. ;input:
  614. ;  ebx - new size
  615. ;result:
  616. ;  [esp+36]:=0 - normal
  617. ;  [esp+36]:=1 - error
  618. ;This function set new application memory size.
  619.     mov    esi,ebx               ;save new size
  620.     add    ebx,4095
  621.     and    ebx,not (4096-1)      ;round up size
  622.     mov    ecx,[0x3000]
  623.     shl    ecx,8
  624.     mov    edx,[0x8008C+ecx]    
  625.     add    edx,4095
  626.     and    edx,not (4096-1)      ;old size
  627.     mov    eax,[0x800B8+ecx]
  628.     call   MEM_Get_Linear_Address
  629. ;eax - linear address of page directory    
  630.     call   MEM_Heap_Lock         ;guarantee that two threads willn't
  631.                                  ;change memory size simultaneously
  632.     cmp    ebx,edx
  633. ;    mov    esi,ebx               ;save new size
  634.     jg     .expand
  635.    
  636. .free:
  637.     sub    edx,ebx
  638.     jz     .unlock               ;do nothing
  639.     mov    ecx,edx
  640.     shr    ecx,12
  641.     add    ebx,std_application_base_address
  642.     call   mem_free_specified_region  ;free unnecessary pages
  643.     jmp    .unlock
  644.  
  645. .expand:
  646.     sub    ebx,edx
  647.     mov    ecx,ebx
  648.     shr    ecx,12
  649.     mov    ebx,edx
  650.     add    ebx,std_application_base_address
  651.     call   mem_alloc_specified_region ;alloc necessary pages
  652.     test   eax,eax
  653.     jz     .failed               ;not enough memory
  654.    
  655. .unlock:
  656.     mov    ebx,esi
  657.     mov    eax,[0x3000]
  658.     shl    eax,8
  659.     mov    [eax+0x8008c],ebx     ;write new memory size
  660. ;search threads and update
  661. ;application memory size infomation    
  662.     mov    ecx,[eax+0x800b8]
  663.     mov    eax,2
  664.    
  665. .search_threads:
  666. ;eax = current slot
  667. ;ebx = new memory size
  668. ;ecx = page directory
  669.     cmp    eax,[0x3004]
  670.     jg     .search_threads_end
  671.     mov    edx,eax
  672.     shl    edx,5
  673.     cmp    word [0x3000+edx+0xa],9 ;if slot empty?
  674.     jz     .search_threads_next
  675.     shl    edx,3
  676.     cmp    [edx+0x800b8],ecx     ;if it is our thread?
  677.     jnz    .search_threads_next
  678.     mov    [edx+0x8008c],ebx     ;update memory size
  679. .search_threads_next:
  680.     inc    eax
  681.     jmp    .search_threads
  682. .search_threads_end:
  683.  
  684.     call   MEM_Heap_UnLock
  685.     mov    dword [esp+36],0
  686.     ret
  687.    
  688. .failed:
  689.     call   MEM_Heap_UnLock
  690.     mov    dword [esp+36],1
  691.     ret    
  692. ;-----------------------------------------------------------------------------
  693. pid_to_slot:
  694. ;Input:
  695. ;  eax - pid of process
  696. ;Output:
  697. ;  eax - slot of process or 0 if process don't exists
  698. ;Search process by PID.
  699.     push   ebx
  700.     push   ecx
  701.     mov    ebx,[0x3004]
  702.     shl    ebx,5
  703.     mov    ecx,2*32
  704.    
  705. .loop:
  706. ;ecx=offset of current process info entry
  707. ;ebx=maximum permitted offset
  708.     cmp    byte [second_base_address+0x3000+ecx+0xa],9
  709.     jz     .endloop              ;skip empty slots
  710.     cmp    [second_base_address+0x3000+ecx+0x4],eax ;check PID
  711.     jz     .pid_found
  712. .endloop:
  713.     add    ecx,32
  714.     cmp    ecx,ebx
  715.     jle    .loop
  716.    
  717.     pop    ecx
  718.     pop    ebx
  719.     xor    eax,eax
  720.     ret
  721.    
  722. .pid_found:
  723.     shr    ecx,5
  724.     mov    eax,ecx               ;convert offset to index of slot
  725.     pop    ecx
  726.     pop    ebx
  727.     ret
  728. ;-----------------------------------------------------------------------------    
  729. is_new_process:
  730. ;Input:
  731. ;  eax - process slot
  732. ;Output:
  733. ;  eax=1 - it is new process
  734. ;  eax=0 - it is old process
  735. ;    shl   eax,5
  736. ;    mov   eax,[second_base_address+0x3000+eax+0x10]
  737. ;    cmp   eax,std_application_base_address  ;check base address of application
  738. ;    jz    .new_process
  739. ;    xor   eax,eax
  740. ;    ret
  741.    
  742. ;.new_process:
  743.     mov   eax,1
  744.     ret
  745. ;-----------------------------------------------------------------------------    
  746. write_process_memory:
  747. ;Input:
  748. ;  eax - process slot
  749. ;  ebx - buffer address
  750. ;  ecx - buffer size
  751. ;  edx - start address in other process
  752. ;Output:
  753. ;  eax - number of bytes written
  754.     pushad
  755.     shl  eax,8
  756.     mov  eax,[0x80000+eax+0xB8]
  757.     call MEM_Get_Linear_Address
  758.     mov  ebp,eax
  759. ;ebp=linear address of page directory of other process.    
  760.     add  edx,std_application_base_address  ;convert to linear address
  761.     test ecx,ecx
  762.     jle  .ret
  763.    
  764. .write_loop:
  765. ;ebx = current buffer address
  766. ;ecx>0 = current size
  767. ;edx = current address in other process
  768. ;ebp = linear address of page directory
  769.  
  770.     call MEM_Heap_Lock           ;cli
  771.     mov  esi,edx
  772.     shr  esi,22
  773.     mov  eax,[ebp+4*esi]         ;find page directory entry
  774.     and  eax,not (4096-1)        ;clear flags
  775.     test eax,eax
  776.     jz   .page_not_found
  777.     call MEM_Get_Linear_Address  ;calculate linear address of page table
  778.     test eax,eax
  779.     jz   .page_not_found
  780.     mov  esi,edx
  781.     shr  esi,12
  782.     and  esi,1023                
  783.     mov  eax,[eax+4*esi]         ;find page table entry
  784.     and  eax,not (4096-1)
  785.     test eax,eax
  786.     jz   .page_not_found
  787.     call MEM_Get_Linear_Address  ;calculate linear address of page
  788.     test eax,eax
  789.     jz   .page_not_found
  790.     mov  edi,eax
  791.     call MEM_Add_Reference_Linear;guarantee that page willn't disappear
  792.     call MEM_Heap_UnLock         ;sti
  793.    
  794.     mov  esi,edx
  795.     and  esi,4095
  796.     add  edi,esi                 ;add offset in page
  797. ;edi = linear address corresponding edx in other process
  798.     sub  esi,4096
  799.     neg  esi                     ;esi - number of remaining bytes in page
  800.     cmp  esi,ecx
  801.     jl   .min_ecx
  802.     mov  esi,ecx
  803. .min_ecx:                        ;esi=min(ecx,esi) - number of bytes to write
  804.     sub  ecx,esi
  805.     push ecx
  806.     mov  ecx,esi                 ;ecx - number of bytes to write
  807.     mov  esi,ebx                 ;esi - source, edi - destination
  808.     add  edx,ecx                 ;move pointer in address space of other process
  809.     push edi
  810.    
  811. ;move ecx bytes    
  812.     test ecx,3
  813.     jnz  .not_aligned
  814.     shr  ecx,2
  815.     rep  movsd
  816.     jmp  .next_iter
  817. .not_aligned:
  818.     rep  movsb
  819. .next_iter:
  820.  
  821.     pop  eax                    
  822.     and  eax,not (4096-1)        ;eax - linear address of current page
  823.     call MEM_Free_Page_Linear    ;free reference
  824.     mov  ebx,esi                 ;new pointer to buffer - movsb automaticaly advance it.
  825.     pop  ecx                     ;restore number of remaining bytes
  826.     test ecx,ecx
  827.     jnz  .write_loop
  828. .ret:    
  829.     popad
  830.     mov  eax,ecx
  831.     ret
  832.    
  833. .page_not_found:
  834.     call MEM_Heap_UnLock         ;error has appeared in critical region
  835.     sub  ecx,[esp+24]            ;[esp+24]<-->ecx
  836.     neg  ecx                     ;ecx=number_of_written_bytes
  837.     mov  [esp+28],ecx            ;[esp+28]<-->eax
  838.     popad
  839.     ret    
  840. ;-----------------------------------------------------------------------------    
  841. syscall_test:
  842. ;for testing memory manager from applications.
  843.     mov  edx,ecx
  844.     mov  ecx,ebx
  845.     call trans_address
  846.     mov  ebx,eax
  847.     mov  eax,[0x3000]
  848.     call read_process_memory
  849.     ret
  850. ;-----------------------------------------------------------------------------    
  851. read_process_memory:
  852. ;Input:
  853. ;  eax - process slot
  854. ;  ebx - buffer address
  855. ;  ecx - buffer size
  856. ;  edx - start address in other process
  857. ;Output:
  858. ;  eax - number of bytes read.
  859.     pushad
  860.     shl  eax,8
  861.     mov  eax,[0x80000+eax+0xB8]
  862.     call MEM_Get_Linear_Address
  863.     mov  ebp,eax
  864.     add  edx,std_application_base_address
  865. .read_loop:
  866. ;ebx = current buffer address
  867. ;ecx>0 = current size
  868. ;edx = current address in other process
  869. ;ebp = linear address of page directory
  870.  
  871.     call MEM_Heap_Lock           ;cli
  872.     mov  esi,edx
  873.     shr  esi,22
  874.     mov  eax,[ebp+4*esi]         ;find page directory entry
  875.     and  eax,not (4096-1)
  876.     test eax,eax
  877.     jz   .page_not_found
  878.     call MEM_Get_Linear_Address
  879.     test eax,eax
  880.     jz   .page_not_found
  881.     mov  esi,edx
  882.     shr  esi,12
  883.     and  esi,1023
  884.     mov  eax,[eax+4*esi]         ;find page table entry
  885.     and  eax,not (4096-1)
  886.     test eax,eax
  887.     jz   .page_not_found
  888.     call MEM_Get_Linear_Address  ;calculate linear address of page
  889.     test eax,eax
  890.     jz   .page_not_found
  891.     mov  esi,eax
  892.     call MEM_Add_Reference_Linear;guarantee that page willn't disappear
  893.     call MEM_Heap_UnLock         ;sti
  894.    
  895.     mov  edi,edx
  896.     and  edi,4095                
  897.     add  esi,edi                 ;add offset in page
  898. ;esi = linear address corresponding edx in other process
  899.     sub  edi,4096
  900.     neg  edi
  901.    
  902. ;edi=min(edi,ecx) - number of bytes to copy  
  903.     cmp  edi,ecx
  904.     jl   .min_ecx
  905.     mov  edi,ecx
  906. .min_ecx:
  907.  
  908.     sub  ecx,edi                 ;update size of remaining bytes
  909.     add  edx,edi                 ;update current pointer in other address space.
  910.     push ecx
  911.     mov  ecx,edi                 ;ecx - number of bytes to read
  912.     mov  edi,ebx                 ;esi - source, edi - destination
  913.     push esi
  914. ;move ecx bytes    
  915.     test ecx,3
  916.     jnz  .not_aligned
  917.     shr  ecx,2
  918.     rep  movsd
  919.     jmp  .next_iter
  920. .not_aligned:
  921.     rep  movsb
  922. .next_iter:
  923.     pop  eax
  924.     and  eax,not (4096-1)        ;eax - linear address of current page
  925.     call MEM_Free_Page_Linear    ;free reference
  926.     mov  ebx,edi                 ;new pointer to buffer - movsb automaticaly advance it.
  927.     pop  ecx                     ;restore number of remaining bytes
  928.     test ecx,ecx
  929.     jnz  .read_loop
  930.    
  931.     popad
  932.     mov  eax,ecx
  933.     ret
  934.    
  935. .page_not_found:
  936.     call MEM_Heap_UnLock         ;error has appeared in critical region
  937.     sub  ecx,[esp+24]            ;[esp+24]<-->ecx
  938.     neg  ecx                     ;ecx=number_of_read_bytes
  939.     mov  [esp+28],ecx            ;[esp+28]<-->eax
  940.     popad
  941.     ret
  942. ;-----------------------------------------------------------------------------
  943. check_region:
  944. ;input:
  945. ;  ebx - start of buffer
  946. ;  ecx - size of buffer
  947. ;result:
  948. ;  eax = 1 region lays in app memory
  949. ;  eax = 0 region don't lays in app memory
  950.     mov  eax,[0x3000]
  951.     jmp  check_process_region
  952. ;-----------------------------------------------------------------------------    
  953. check_process_region:
  954. ;input:
  955. ;  eax - slot
  956. ;  ebx - start of buffer
  957. ;  ecx - size of buffer
  958. ;result:
  959. ;  eax = 1 region lays in app memory
  960. ;  eax = 0 region don't lays in app memory
  961.     test ecx,ecx
  962.     jle  .ok
  963.     shl  eax,5
  964.     cmp  word [0x3000+eax+0xa],0
  965.     jnz  .failed
  966.     shl  eax,3
  967.     mov  eax,[0x80000+eax+0xb8]
  968.     test eax,eax
  969.     jz   .failed
  970.     call MEM_Get_Linear_Address
  971.     push ebx
  972.     push ecx
  973.     push edx
  974.     mov  edx,ebx
  975.     and  edx,not (4096-1)
  976.     sub  ebx,edx
  977.     add  ecx,ebx
  978.     mov  ebx,edx
  979.     add  ecx,(4096-1)
  980.     and  ecx,not (4096-1)
  981. .loop:
  982. ;eax - linear address of page directory    
  983. ;ebx - current page
  984. ;ecx - current size
  985.     mov  edx,ebx
  986.     shr  edx,22
  987.     mov  edx,[eax+4*edx]
  988.     and  edx,not (4096-1)
  989.     test edx,edx
  990.     jz   .failed1
  991.     push eax
  992.     mov  eax,edx
  993.     call MEM_Get_Linear_Address
  994.     mov  edx,ebx
  995.     shr  edx,12
  996.     and  edx,(1024-1)
  997.     mov  eax,[eax+4*edx]
  998.     and  eax,not (4096-1)
  999.     test eax,eax
  1000.     pop  eax
  1001.     jz   .failed1
  1002.     add  ebx,4096
  1003.     sub  ecx,4096
  1004.     jg   .loop
  1005.     pop  edx
  1006.     pop  ecx
  1007.     pop  ebx
  1008. .ok:
  1009.     mov  eax,1
  1010.     ret
  1011.    
  1012. .failed1:
  1013.     pop  edx
  1014.     pop  ecx
  1015.     pop  ebx
  1016. .failed:
  1017.     xor  eax,eax
  1018.     ret
  1019. ;-----------------------------------------------------------------------------
  1020. new_sys_ipc:
  1021. ;input:
  1022. ;  eax=1 - set ipc buffer area
  1023. ;    ebx=address of buffer
  1024. ;    ecx=size of buffer
  1025. ;  eax=2 - send message
  1026. ;    ebx=PID
  1027. ;    ecx=address of message
  1028. ;    edx=size of message
  1029.     cmp  eax,1
  1030.     jnz  .no_ipc_def
  1031. ;set ipc buffer area    
  1032.     mov  edi,[0x3000]
  1033.     shl  edi,8
  1034.     add  edi,0x80000
  1035.     cli
  1036.     mov  [edi+0xA0],ebx          ;set fields in extended information area
  1037.     mov  [edi+0xA4],ecx
  1038.     sti
  1039.     mov  [esp+36],dword 0        ;success
  1040.     ret
  1041.        
  1042. .no_ipc_def:
  1043.     cmp  eax,2
  1044.     jnz  .no_ipc_send
  1045. ;send message    
  1046.     cli
  1047. ;obtain slot from PID    
  1048.     mov  eax,ebx
  1049.     call pid_to_slot
  1050.     test eax,eax
  1051.     jz   .no_pid
  1052.     mov  ebp,eax
  1053. ;ebp = slot of other process    
  1054.     shl  eax,8
  1055.     mov  edi,[eax+0x80000+0xa0]  ;is ipc area defined?
  1056.     test edi,edi
  1057.     jz   .no_ipc_area
  1058.     mov  esi,[eax+0x80000+0xa4]  ;esi - size of buffer
  1059.     push dword -1                ;temp variable for read_process_memory
  1060.     mov  ebx,esp
  1061.     push ecx
  1062.     push edx
  1063.     mov  ecx,4                   ;read 4 bytes
  1064.     mov  eax,ebp
  1065.     mov  edx,edi                 ;from beginning of buffer.
  1066.     call read_process_memory
  1067.     mov  eax,[esp+8]
  1068.     test eax,eax
  1069.     jnz  .ipc_blocked            ;if dword [buffer]<>0 - ipc blocked now
  1070.     add  edx,4                   ;move to next 4 bytes
  1071.     mov  eax,ebp
  1072.     call read_process_memory     ;read size of occupied space in buffer
  1073.     sub  esi,8
  1074.     sub  esi,[esp]
  1075.     sub  esi,[esp+8]             ;esi=(buffer size)-(occupied size)-(message size)-(header of message size)
  1076.     js   .buffer_overflow        ;esi<0 - not enough memory in buffer
  1077.     mov  esi,[esp+8]             ;previous offset
  1078.     add  dword [esp+8],8
  1079.     mov  edi,[esp]
  1080.     add  [esp+8],edi             ;add (size of message)+(size of header of message) to [buffer+4]
  1081.     mov  eax,ebp
  1082.     call write_process_memory
  1083.     add  edx,esi                
  1084.     sub  edx,4                   ;move to beginning of place for our message
  1085.     mov  eax,[second_base_address+0x3010]
  1086.     mov  eax,[eax+0x4]           ;eax - our PID
  1087.     mov  [esp+8],eax
  1088.     mov  eax,ebp
  1089.     call write_process_memory    ;write PID
  1090.     mov  ebx,esp                 ;address of size of message
  1091.     mov  eax,ebp
  1092.     add  edx,4
  1093.     call write_process_memory    ;write size of message
  1094.     add  edx,4
  1095.     pop  ecx                     ;ecx - size of message
  1096.     pop  eax
  1097.     call trans_address
  1098.     mov  ebx,eax                 ;ebx - linear address of message
  1099.     add  esp,4                   ;pop temporary variable
  1100.     mov  eax,ebp
  1101.     call write_process_memory    ;write message
  1102.     sti
  1103. ;awake other process    
  1104.     shl  ebp,8
  1105.     mov  eax,ebp
  1106.     or   [eax+0x800A8],dword 0x40
  1107.    
  1108.     cmp  dword [check_idle_semaphore],20
  1109.     jge  .ipc_no_cis
  1110.     mov  dword [check_idle_semaphore],5
  1111. .ipc_no_cis:
  1112.     mov  dword [esp+36],0
  1113.     ret
  1114. .no_ipc_send:
  1115.     mov  dword [esp+36],-1
  1116.     ret
  1117. .no_pid:
  1118.     sti
  1119.     mov  dword [esp+36],4
  1120.     ret
  1121. .no_ipc_area:
  1122.     sti
  1123.     mov  dword [esp+36],1
  1124.     ret
  1125. .ipc_blocked:
  1126.     sti
  1127.     add  esp,12
  1128.     mov  dword [esp+36],2
  1129.     ret
  1130. .buffer_overflow:
  1131.     sti
  1132.     add  esp,12
  1133.     mov  dword [esp+36],3
  1134.     ret
  1135. ;-----------------------------------------------------------------------------    
  1136. trans_address:
  1137. ;Input
  1138. ;  eax - application address
  1139. ;Output
  1140. ;  eax - linear address for kernel      
  1141.     add   eax,std_application_base_address
  1142.     ret
  1143. ;-----------------------------------------------------------------------------    
  1144. new_start_application_hd:
  1145. ;eax - file name (kernel address)
  1146. ;ebx - file name length
  1147. ;ecx - work area (kernel address)
  1148. ;ebp - parameters
  1149.     pushad
  1150.    
  1151.     mov    esi,new_process_loading
  1152.     call   sys_msg_board_str     ;write message to message board
  1153.    
  1154. ;lock application_table_status mutex
  1155. .table_status:
  1156.     cli
  1157.     cmp    [application_table_status],0
  1158.     jz     .stf
  1159.     sti
  1160.     call   change_task
  1161.     jmp    .table_status
  1162. .stf:
  1163.     call   set_application_table_status
  1164.    
  1165.     push   ebp
  1166.     push   ebx
  1167.     push   eax
  1168.     push   ecx
  1169.     call   find_new_process_place ;find new process slot
  1170.     sti
  1171.     test   eax,eax
  1172.     jz     .failed
  1173.    
  1174. ;write application name    
  1175.     mov    eax,[esp+4]
  1176. .find_last_byte:
  1177.     cmp    byte [eax],0    
  1178.     jz     .find_last_byte_end
  1179.     inc    eax
  1180.     jmp    .find_last_byte
  1181. .find_last_byte_end:    
  1182.     lea    esi,[eax-11]          ;last 11 bytes = application name
  1183.     mov    edi,[new_process_place]
  1184.     shl    edi,8
  1185.     add    edi,0x80000
  1186.     mov    ecx,11
  1187.     cld
  1188.     rep    movsb                 ;copy name to extended information about process
  1189.    
  1190. ;read header    
  1191.     mov    eax,[esp+4]           ;file name
  1192.     mov    esi,[esp]             ;work area
  1193.     mov    ecx,1                 ;read from first block
  1194.     mov    edx,1                 ;read 1 block
  1195.     call   read_hd_file
  1196.     test   eax,eax
  1197.     jnz    .cleanfailed
  1198.  
  1199.     mov    esi,[esp]
  1200. ;check menuet signature    
  1201.     cmp    [esi+1024+0],dword 'MENU'  ;read_hd_file function write file to +1024 offset
  1202.     jnz    .cleanfailed
  1203.     cmp    [esi+1024+4],word 'ET'
  1204.     jnz    .cleanfailed
  1205.     add    esi,1024
  1206.     mov    edi,0x90000
  1207.     mov    ecx,512/4
  1208.     cld
  1209.     rep    movsd                 ;copy first block to 0x90000 address for get_app_params function
  1210.     call   get_app_params
  1211.     test   esi,esi
  1212.     jz     .cleanfailed
  1213.    
  1214.     mov    eax,[new_process_place]
  1215.     call   create_app_cr3_table  ;create page directory
  1216.     test   eax,eax
  1217.     jz     .cleanfailed_mem
  1218.    
  1219.     call   MEM_Get_Linear_Address
  1220.    
  1221.     mov    ebx,std_application_base_address
  1222.     mov    ecx,[app_mem]
  1223.     add    ecx,4096-1
  1224.     shr    ecx,12
  1225.     mov    edx,eax               ;edx - linear address of page directory
  1226.     call   mem_alloc_specified_region ;allocate memory for application
  1227.     test   eax,eax
  1228.     jz     .cleanfailed_mem
  1229.    
  1230.     add    edx,(std_application_base_address shr 20)
  1231.     mov    eax,[edx]
  1232.     and    eax,not (4096-1)
  1233.     call   MEM_Get_Linear_Address
  1234.     push   edx                   ;save pointer to first page table
  1235.     mov    edx,eax
  1236. ;read file
  1237.     mov    ecx,1
  1238.     xor    ebp,ebp
  1239. .loop1:
  1240. ;[esp] - pointer to current page directory entry
  1241. ;edx - pointer to current page table
  1242. ;ebp - offset in page
  1243. ;ecx - current cluster
  1244.     push   edx
  1245.     mov    eax,[esp+12]          ;file name
  1246.     mov    ebx,[esp+16]          ;file name length
  1247.     mov    esi,[esp+8]           ;work area
  1248.     mov    edx,1                 ;number of blocks to read
  1249.     push   ecx
  1250.     push   ebp
  1251.     cli
  1252.     call   read_hd_file
  1253.     sti
  1254.     pop    ebp
  1255.     test   eax,eax
  1256.     jnz    .endloop1             ;check io errors
  1257.    
  1258.     mov    esi,[esp+8+4]         ;work area
  1259.     add    esi,1024
  1260.     mov    eax,[esp+4]           ;current page table
  1261.     mov    eax,[eax]
  1262.     and    eax,not (4096-1)        
  1263.     call   MEM_Get_Linear_Address;calculate linear page address
  1264.     lea    edi,[eax+ebp]         ;add page offset
  1265.     mov    ecx,512/4
  1266.     cld
  1267.     rep    movsd                 ;copy data
  1268.    
  1269.     pop    ecx
  1270.     inc    ecx                   ;next block
  1271.     mov    eax,[app_i_end] ;todo: precalculate ([app_i_end]+4095)/4096
  1272.     add    eax,512-1
  1273.     shr    eax,9                 ;calculate application image size
  1274.     cmp    ecx,eax
  1275.     jg     .endloop11
  1276.     pop    edx
  1277.     add    ebp,512               ;new offset
  1278.     test   ebp,4096
  1279.     jz     .loop1
  1280.     xor    ebp,ebp
  1281.     add    edx,4                 ;go to next page
  1282.     test   edx,(4096-1)
  1283.     jnz    .loop1
  1284.     add    dword [esp],4         ;go to next directory entry
  1285.     mov    eax,[esp]
  1286.     mov    eax,[eax]
  1287.     and    eax,not (4096-1)
  1288.     call   MEM_Get_Linear_Address
  1289.     mov    edx,eax
  1290.     jmp    .loop1
  1291. .endloop1:
  1292.     add    esp,4                 ;pop ecx
  1293. .endloop11:
  1294.     add    esp,4+4               ;pop edx, pop edx
  1295.    
  1296. ;add_app_parameters
  1297.     add    esp,12                ;now pointer to parameters is on the top of the stack
  1298.     call   new_start_application_fl.add_app_parameters ;start process
  1299.     mov    [esp+28],eax
  1300.     popad
  1301.     ret
  1302.    
  1303. .cleanfailed_mem:
  1304.     mov    esi,start_not_enough_memory
  1305.     call   sys_msg_board_str    
  1306. .cleanfailed:                    ;clean process name
  1307.     mov    edi,[new_process_place]
  1308.     shl    edi,8
  1309.     add    edi,0x80000
  1310.     mov    ecx,11
  1311.     mov    eax,' '
  1312.     cld
  1313.     rep    stosb    
  1314. .failed:
  1315.     add    esp,16
  1316.     popad  
  1317.     mov    eax,-1
  1318.     mov    [application_table_status],0
  1319.     sti
  1320.     ret
  1321. end if
  1322.